CA1248147A

CA1248147A - Determining of the amount of material delivered each operational cycle of a shovel loader

Info

Publication number: CA1248147A
Application number: CA000511025A
Authority: CA
Inventors: James R. Blair; Tomothy W. Riley
Original assignee: Acet Ltd
Current assignee: Acet Ltd
Priority date: 1985-06-07
Filing date: 1986-06-06
Publication date: 1989-01-03
Also published as: GB2187561A; GB2187561B; DE3675361D1; JPS63500046A; ZA864284B; EP0229083A1; EP0229083A4; GB8702246D0; EP0229083B1; WO1986007399A1; US4809794A

Abstract

ABSTRACT

A method and apparatus for measuring the quantity of material delivered per cycle by a shovel loader having a bucket 22 that is moved between loaded and unloading positions. During the movement of the bucket in either direction between said positions, determinations are made of the location of the bucket with respect to two spaced points 27 and 17 on the structure 15 supporting the bucket. At the same time determinations are made as to the strain at a particular location in the support structure 15, that strain being related to total weight of the bucket and its contents. The bucket position determinations and the strain determinations are each provided as inputs to a processor 95 programmed to calculate therefrom the weight of the bucket and contents, when loaded and loaded to thereby provide the weight of material delivered.

Description

lZ~ 7 -- 1 ~
THE DEl~aloNING OF lHE AMCUNr OP M~TERIAL
DELrVERED EACH OPERATION~ CYCLE OF A
SHCVEL LOADER
This invention relates to ~he determining of the amount of material delivered each operational cycle of a shovel loader. In paxticul æ the invention ræla~es to effecting such determm ation in regard to a 6hovel loader camprisiny a base, a platform supported on ~he base for rotation relative thereto about a vertical axis, a boom connected to the platform at the lo~er end and at an upper portion to a stay structure maunted on the platform so the boom exte~ds upwardly and outwardly fram the platform, and a bucket supported suspended fram the bo~m and displaceable therefrom in a vertical and horizontal direction.
It is desirable for a numk2r of reasons to be able to determ me ~he quantity of material delivered ky a sh~vel lcader both frc~m the point of view of material delivered per oEerational cycle of the loader and total q~antities o~e~ small and large ~s of cycles.
~art frc~n ~;ainir~ l he total quarrtit:y of material mov2d 15 in a day or a Ehift, w~ loadir~ vehicles ~y a shovel, it is in~portant to ensure the truck is n~:rt under or over lo~d. Un~lerloading is wasteful ~n regard to vehicle usage, ~ overloading i~ detrimental to véhicle wear an~l overall life.
It is there~ore ~e ~bject of the present irn~ent.ion to provide a method an~l apparatus that is e~feccive in meas ~ir~
~uantity of material delivered each oparating cycle o~ a shovel loader, ha~ing regard to tha onvlronment in ~hich the shcvel lo~der operates and variou~ ~actors in~luencing the accuracy o~ such ~ ements.
With thl~ o;b~ect in vi~w there is provided a methcd o~
mea~uring the quantity o~ material deli~er0d p~r cycle by a shovel loader having a buch~t to hold ~ material to be deliversd the b~cket being m~vable between a 1 ~ and unloadin~ positions, said bucket being supported ~rom a structurs dur ~ ~ovement between said pcsitions, said m~hod ocmprising determ1ning the position of the bucket in respact to a sel ~ location on said structNre in the form of a processable position signal a~ one or ~ore Lntervals dNring said movement, determdndng the load at a selected location within said structure whÆre the load is related to the nass o~ the bucket and-bucke~ contents in the form of a processable load signal at said interval or intervals, an~ processing sald position and load signals to ' ~ .

~Z~8~

determine the mass of the bucket and bucket contents at said interval or i~tervals.
More specifically there is provided a method of measurin~ the quan~ity of material delivered pex cycle by a shcvel loader comprising determlm ng in the form of electrical signals the position of the bucket with respect to a selected locatian and the load at a selected location in the kcom ox stay structure ~t one or a number of inteLvals in the mavement of the boom frcm a bucket loading to a bucket unloading position, pravi~lng mputs, generated by said signals to an electronic processor programmed to calculate therefrom the tstal w~ight of the buck~ and contents at each interval, making further such determinations and inputs to the processor at onz or a number of intervals in the m~vement vf -the bucket in the reverse direction between said position~ and processing said inputs in the processor to provide a difference between the weight of the ~ucket durm g the two m(7v~ts.
By determdnin~ the difference between the weight of the loaded bu~ket as it moves to the unloading position and weight of the empty bucket as it returns from the unloadlng po6ition, the weiyht of the oonten~s o~ the bucke~ actually deposit~d is a ~ ained.
Preferably the processor de ~ s an average o~ the weights calculated durlng the respecti~e mcvements and prcvidQs a difference in these averages as the weight o~ the con~ents deposited by the ~ et.
Conv ~ ently the determination~ are made at predetexmins time intexvale during the m~vement o~ ths bocm in each direction. The time intervals b~tween the determinations are preferably equal.
qhes~ weight determinations may be initiated and terminated in response to suitable parameters, su~h as the pasition o~ the bocm xelative to the base of the loader, or the angular velocity or acceleration o~ ~he bocm relative to the loader base.
Conveniently ~he m i~lation e~ the ~ d the determination of t,he weigh~ of the loaded bucket may be in response t~
the bucket oocupying a selected position rela~ive to the boom that ls indicative tha~ the loading of the ~ucket has b~en ca~plated.
~he termination of weight daterminations may similarly be in resp~nse to t'hs bucket occupy ~ a fur~her selectel po6ition ~elati~e to ~he bo~m indlca~ing the bucket is ~ to dis ~ e its load. Ihe initiation and terminati~n o~ the determination o~ the weigh~ o~ the unloadel bucket are similarly in response to ~elected positions in the movement of the bucket and~or boom.
It has been fcund khat the aocuracy of the determination of the weight of the load discharged is increased if ~he averaging of the de ~ a~ions of weight of the loadel and unloaded bucket, does not include tha de~erminations at or near the respective ends of the respective mcvements of the boom, particularly at the ccmmencement of the mçvements. This is because at these periods sukstantial kinetic load may be experienced and thesQ loads may fluctuat2 significantly wi~hin those pQriods. A~cor~ingly, it is preferable to exclude from the averagLng step a n ~ of ~he weights calculat~d a~ one or b~h - ends of the respective m~vemn~ of the boom.
The position of the kucket relative to the boom may be det ~ by the mea~un=mcnt of the diskance of a reference point on the bucket frcm two fixed points on the koom, one of which may be the piv~k axis of the connection betwe~n the boom and t~e axm ~ ing the bucket.
Conveniently the bucket is ccupled t~ a rigid member pivokally oonnected to both the buck2t and the boam with the effective length of ~he member betwe~n these piv~k connecticns adjustable. The bucket is also muspended from a sheath at the upper end of the bcom, by a cable or cables. The ~ et is raised or lcwered by cperation o~ a winch drum about whlch the cable or cables are w~und.
The position of ~ha ~ et relative to the kcam ~ay be a~certained using sui~able ~ensor3 which prcvid~ respective ~ignal5 to the proce~so~ indl~a~ing the line~r displacement o~ a re~erenoe point on the bwcket ~ram ~hs connectian o~ the member ko the boom anl the len~th o~ cable hetween the shRa~h ~ the kucX~t. Ihe processor is progrommod to dbter~inc ~ro~ these 8ignal8 the c~ro ~ ate~ of the ce~re of gravity o~ the bucket with respec~ to an appr~prlatQ fLxed reference on the loader platform or kocm.
Strain gauges or ~ther suitable load sensing m~ans ara pr wided to generats a signal having a know.n relation to the ~otal w~igh~ supported by tha ~oom. The strai~ gau~es or s2nsing m~ans may be arr3nged to determin~ th~ strain in a ~elected sectiQn of the koom or ~he stay structure in~erconnect~d between ~h~ boom anl th~ loader pla~form. Ihe elec~ronic processor is progrl~med to calcula~e from thi5 signal, and ~he signalg ~eceived in~icated the position o~ the lZ48147 bucket, the total weigh~ ~ orted by the koom, from which the tokal weight of the bucket and its con~e~ts is derived.
The processor is further prr3rsmmed to ~ake a series of such calculations when the kucXet is loaded and after deposit of the load in any one cycle, an~ then determines the dif~erence between the average loaded and unloaded weight supp~rt by the boom to achieve the weight of material dRliver0d by the loader each cycl~
In many shovel loader3 kinetic forces arising from the mav ~ t of such ccmponent as ~he -~ucket, ~ucket arm, boqm, will give rise ko stresses in ~he structural member in which the strain is be m g n~m3d. Accordingly in order to correct for these kinetic forces in the ~ucke~ load determinations, the linear and angular velocity and acceleration of major co~ponents, ~uch as t~e bucket and ~he plat~orm supForting the boom, ar~ Eer~md and fed to ~he processor. me pr~cessor is prcgra=med with static informa~ion rlgardin~ the mass of the relevan~ components, and the physical relation thereof t~ the structural memker, so that, with sensed information re3lrling the velocity and/or acceleration experienced by the comp~nents, the processor can effect the ncceselry ~ tion for kinetic forces in detcrmlning the bucket load.
~ n example of such forc~s ~ocuntsred during~ the m~vement o~
the bNcket from the 1 ~ to the dumping positio~, where that m~vem~nt i~ a ~winging mavement about a vertical axis, is the centri~ugal force~ acting cn ths bucket, boo~ and okher componRnt hav~ng rota~y ~okion. It wlll be appreciated that the kinetic ~orces tha~ induced BtXain~ in ~h~ et~lY~ ral membQr, whÆrein strains are ~ or load d~terminations, will be depen~ent on th~ overall physi~al construction o~ the sh~vel loader~ Hcwev~r, the relevant forces can readily ba identified by suit~ble analys~ of ths structure, and appropria~s proar~mming inGorporatad in the proDessQr to ~ te for these ~orces in the bucket load d~tcrmin~tions.
The position of ~he bucXet relative t4 the boom may ke determins~ by suitable electronic sensors such opkical encoders. As previously referred to the bucke~ may be ccupled to a rigid me~ber pivokally connected to both the bucket and the bocm with the ~ffective 0~ th8 m~mber be~ween these pivot oonnecti~ns ad~ustabl8, and ~he bucket also ~uspended from a sheath at thQ upper end of thQ boom, : by a cable or cables coupled to a winch drum. A~ordingly, th~ length . ~
' , ~Z~ 7 of cable between the bucket and the sheath is a controlling factor in the position of the bucket relative to the bocms The winch drum is driven by an electric mDkor thrcuyh suitable gear train, and an Gptical encoder is cc~pled to the gear train so the signal output therefm m is relat~d to the length of cabla between the sheath and the bucket.
elec~ric motor is provided ccupled via a suitable speed reduction, to a drive mechanism that extends the member relative to the boom, and an encoder is coupled to the drive so the ro~ation ~hereof is proportlonal to the degree of extensio~ of the memb2r. The ou~put f~om the tw~
encoders ma~ be fed t~ the electxonic processor through, if necessary, apprc~riate ampli~iers, and the c~mputer program can determin~ from t]hese sign31s the actual.dispo~ition o~ the centre of gravity of the bucket relative to a sel ~ referenoe point on ~he boom, such as the lcwer point of connectian of the bocm to the platform or shovel loader, or the upper point of connection of the boom to the stay StrUGtUre.
In this regarl, it is to be understood that the boom pr~marily retains a fiKed position rela~ive to the platf~rm during the no~mal operation of the shovel loader. Ho~ever, if the constructions of the shavel loa ~ is such that the ~ position may be varied during cperation, then a fhrther 2nooder wculd be prcvided to produce a ~ignal to indicata the angular di~position o~ the boam to the platfo~m, and that signal w~uld b~ a further input to ~h~ prosessor, which would be progr~mmed to also take into acccunt thls inclina~ion wh~n determining the position of tbe b~cket. qhe cutput of such an encoder m~y al~o be processed to provided DeaEurcment of the velocity andyor acceleration of ths various 5tructural ccmponrnt ~or thb purpose of determlnin~ kinetic ~orce.
No ~ ly, the upper portion of the bccm i8 c=nnectel to th~
9tay 5tructur3 by a rigid or fl ~ le ~ r or member3, which are arranged so as to ba under tension under all ~perating conditions. In the alternativa cons~ruction where~n the inc}ination of the bo~m may ke adjustable, these tension ~ may also be in the form of cables, ~ich can be ext~ed or retracted as req~ired. rhe tension m~, whethQr of a fixed or variable length, is oYnn3cOed to or pas~ed around a rigid strut or stay rigidly secured to the platfor~. Ihe stra~n m ~e tansion m~ or ~ strut or stay th~ has a calallable : relationship with ~h~ load ~ orted by the boam. It is ~hQreforQ
poss~ble to locate a suitablQ strain or stress sensing device on the ; .;, , '7 tension melr~ or an<~ther appr~priat~ ~er or me~ in ~a s~ay strucl~, ~idh will pr~duce a signa~ havir~ a ralculable relatic~ip to ~he wei~ht s~ported by the boam. It is preferaJ31e for ~he sensor to ba atta~ to a rigid m~ rather than a flexible ~[~er, as this red~lced the camplexity of the relati ~ ihip be~we ~ ~ e stress or strain in tha~ member and the load gupported by the boom~
Ihe intervals at which the readings are ~aken to record the position of the bucXQt, and the strain in the rælevant ~ of the stay structure, are identical. qhe initiation of recording and processing of budXet posit~on and strain readings iS determined ~y sensing ~he cc=oeDoe~ent of the ~ovement of the boo~ beyond a predetermined poLnt in its rotary movement relakive to the plakform, or the ~cvement of the bN~ket beyond a preselected locaticn relative to ~ boGm, such location being ~Plectel as one whi~h th2 bucXet oocupie~
dNr ~ transit, and doe~ nct occupy during normal oollectiom of the material into the budket.
Simil~rly, at the depoeit end of the ~ve~ent of the bucket, a sensor is provid ~ to determine the cc=-I~y~ement of depo6it ~ of the material. Such a sensor may be related to the release of ~he door of the bud~et to dÆposit the materlal.
The initiatian and t ~ tion of the r~cording of ~he si~nal indicating the bucket position and s~rain in the stay e~lucturo may be in reqponse to the pl~tfo~m supporting the boom passing thrcugh select0d angular rela~ionship~ to the shovel base. The r~katlon of the 25 plat~onn relative to ~ base is adhieved }~y an elect~ia ~tcr driving t:~ a ~uitable gear bo~c. A ~table e~od~ may be c~led to thls driva train, via a h~r~ g~ar ~iar~ if n~s~ry, so ~e e~i~ects c~e r~volution ~or a c~plet~ revolutian of the plat~orm.
Acoor~i~gly, a ~ apprapriatQ calibxatlon ~B reJative ar~ular position o~ thQ ~lat~or~, and ~ of the bcom m~unk~d thQneon, can ke sensed by th~ prncessor on the basis o~ the output ~rom th2 encoder.
This arrang ~ enables the p~ocessor to initiate and terminate the reoording of the signals indicating the bucket pcsiti~n and stay struct~r3 strain within a selec~d range of an~ular relationships between the boGm and the`shovel base. Ihe particular range being selected to withln the rang~ of move~ent between the loadlng and unloading position o~ the bucket. qh~ direction o~ ~he changes in the encodRr re~ding, ie. increasing or d~creas m g, will :;~2'1~

ir~icate to the processor the ~ion o~ n~vemer~t o~ ~e boam.
~ ere is also provided ~ the pres~t i~ tian in a shavel loader havi~ a bu~ke~ su~ported ~r~n a s~, the ~tructure being able ~ locat~ ~he h~et in re~ective loaded and unloadir~
5 positions, and apparatus for measurin~ the q~anti~y o~ mat~rial del~vered ~y ~e bu~cet per shavel c~ycle, said aEparatus ~isir~
means to da~ninQ the posi~ion of t~e ~iket with re~:pect to a selected location in the ~n:~o at o~ or more i~als during said ~v~3n~ of the hldket, mearLs to pravide a pr~cessable po6ition signal 10 iT~licative o~ the det~ position o~ the buihet, mears to det~
the load at a sel~t~d locatiaql within the structu~e ~8 the load is rela~ed to the mass of the bucil~et arx3 budce~ s at said or~e ~r m~re intervals ~uring said mov~c of ~he buc~et, means to pr~ a pmcessable load signal in~icat~ve of ff~e determin~l load at said 15 loc~tion, an~ processor means to reaelve ~d positicln and load signals and dete~mine 1~herefr~m the mass of the ~het a~l ~e~ cc~ents.

foll~ des~ipticQ~ of a~plication ~reof to a knoc~ d~ pe of ~hovel loader and with referer~ to ffle aoca~ing dra~ri~s.
~ ~he drawings;
Figure 1 iE~ a simplified draw~g ~ the general c~tru~tion layaut of l~he di~per Ehovel load~.
Figuro 2 is a diagr~atic repr~tatl~ of th~ various sensor~ and. }~roces~or~ used in effe~ t~2s dipper load 25 determ~ation~.
Figure 3 ancl 4 ~og~ are a logia diagr~ ~r~ ffls p~m d ff~ sor.
Figure 5 i~ a diagra~a~c repres~tatian o~ an ~ptical er~r fcr signalir~ to ~e ~or t~a positi~ o~ vari~s 30 c~ of t~ ~vel loa~r.

~he well ha~ n;tn:ction ca~ly referred to as a dipper shovel load~ havel loader c~prises a ~ILibilQ base 10 Sl~O~I
drive trac~ks 11, and havin~ ~orted therecn ~ ~h0 turntable 12, 35 a ma~Y dadC 13. Ihe tun~lQ 12 permits ~ull 360 l~G~tiC~ of the madh:Lr~y de~c ~elative to the base.
The bo~ 15 is pivc~tally ~nneot~ at 16 to ~he Irachinery de~c, and carrie~ a~ t~ upper end. a cable ~eat~h 17. ma boc~ i~ held ~2~ L7 in a fixed upwar~y ar~l autwardly exter~ relatioql to the de~c by the tensia~ cables 18~ ~i.ch are anchored to the bad~ stay 19 of the stay struct~re 20, xigidly ~unt~d ~ the mac~y d~c 13.
qhe buc~lcet or di~per 22 is su~ed 1~ ff~e cable 23 frcm ~he 5 ~heath 17, ~e cable bein~ ar~ored to the win~ n 24 mo~ted on ffle machinery deck 13. ~e di~ has an arm 25 rigidly attac~hed thereto, wi~h ~he diFpe3~ arm 25 slid~bly s~ortecl in ~e s~e blo~ik 26, ~ich is pivotally n~ted c~ the bo~n 15 at ~7. I~e diF~ a~n has a ra~
~h forma~i~ thereoII (n~ ~) ~ibh er~agPs a drive pinion, (n~t 10 ~ha~) ~ted in ~ sa~le bloc~k 26. I~e drive pinian ~s driven ~r an electri~ m~tor an~ tr~i~ion ~it 28 to eP~ect ~sicn or re~action of ~he diE~per arm 25 relative to t~he sa~le blo~c 26.
An engin~ driven electric generator is mc~ on the m~chir~y de~c to pr~ide ~ to ~i~ electric mcrtor~
15 drive the wir~ m 24, saddle blo~k tr~issian ~it 28, ard machinery d~k t~rntable 12. As previously e~lained, ff~e pOSitiCll of the diFper 22 relative to a selected f.~ced reference point on the boarn 15 may be detern~ ~y knawin~ the ext~ of projection of the dipper a~n 25 with ~t to ~e saddls bl~c 26 and ffie effective len~ oP
20 ~ ca~le 23 between ff~ Eiheath 17 ar~ t~e di~per 22. I~e abov~
described basic cons'cruc ticll o~ ~ ~vel loader is widely }cw;m and used and ~ur~ details O:e the ~Istm~tion ar~ not pravided a~3 they are well ~awn in ~ art.
In th~ ~ati~ of ~ l loader a basic series of 25 r=t~ o:~ ths diFper an~ ~iated with each delivery of matf~rial to the tru~c or ~ lil~. A11:ha~ ~ ~pe;rator ma~ rfcsrm o~her cperations with ~e diE~per be~ween deliveries of ~ ma~erial to ff~
t;rucdc, it i~3 poE;sible to re~gnlso ~ ~e loadex is d~liverin~

30 loos~ material in tho loadir~ v~cinit:y or carry~ng ~t su~ ~ther cperations t~at are n~t dir~ct3y i~volved in a 1~ s~ce.
~e s~ of loadi~ ~perations ar~:
1. I~adi~ the di~per with material wh~e~ the dipE~er is in a law~ed positian.

2. Raisi~ the di~per to an eleva~ position.
vertlcal axi~ f~m a diggirx3 ~sition to an ~oadir~ po~i~i~.

.. .. .

_ 9 _ p~SitiCQ~. .
5. Re~rni~ the di~per fr~n the unloadir~ position to the digg~r~ position.
6. Closing t~he dipper door ~en the dipper is mavirg tawards the diggin~ position.
As, in ~he preferred ~ra~on, the load weighing proce~ure is carried ~c ~ile the diE~per is swingin~ in the raised position, it ~s cornre~ier~t to arrar~e that prwessor only places in store dip~er load calculations made whilst ~e dip~ ~ in a raised position. mis 10 raised positi~ can ~e readily determir~d ~y ~e an~ular relationship betwe~ the di~per arm 25 and ~e boam 15. Ihe processo~ can determine this ar~le from a calculatioql based c~ ~ e len~th of cable played alt from the win~h drum 2~ and the position of the dipper ~rm 25 relative ~o ~he saddle block 26 determined by the position of the rack on the dipper ~rm relative to t~e driving pinion, and load calculations made whilst in that posi~ion wculd not be considered in calculatin~ the loaled or unlo ~ weight of the dipper.
Determination that the dipper is ~ Lng can ~e cbkained by detecting rokation o~ the ~ driving the t ~ le 12 or of a 20 ~omponent in the turntable driva trans=lssion. This is convem ently achieved ~y an cpkic 1 encoder uni~ lncorporating a me~ber ccuple~ to t~e turntabla drive to rnkate in a ~ixRd sFeed rela~ion to the ma~hinery de~c r~tati~n. ~ exterlt o~ ular mavement o~ the ma~ de~, and. ~ a~ular velocit~r and acaelerdtion t~ereo~ can 25 be calcula~d 1~ the pra;ess~ frc~ ths signals r~ei~red fr~ th~
e~. lhQ general ~:ctlon ar~l c~ation of t:~e ~tical encoder is ~ rib~d hereir ~ .
Ihe prccessor is thus able to de ~ e, fr~m the turnt~ble enooder, when the boo~ 15 and dipFer 22 ars swinging between ~he digging anl dumpin3 pcsltions in ai~her direction, and mak~ the dipper load calcula~ions during those pericds. As previcusly referrel to these calculation~ are ~ade at fixel time i~s, dur~ the swir~ing ~ve~, an~l calallatiorls m~ ~urir~r t~e ini~ial arxl terminal p~rtic~ of the s~ i~3 n~vemen~ are discarded ~ ~e load 35 averagir~ to avoid ~he effects o~ lcine~ic forces in the ~vel loader Stl:UCtU~. ~e load ~cllla~ion to l~e disc~rded can be c~ted frca~
the ini~ and ~inal si~nal received fr~m t~ tun~table e3xcder in each s~ing mov~t~

4~

A si~nilar ~tical ~ uni~ is iz~orpora~edL in the drive of the winc~ n 24 so tha~ the ler~ of cable played out fram ffle win~ dr~n can be calculated fr~n ~he rotation of the dnm. I~e processor can calculate îram this the di~tar~e betwe~ the c~n~xe of 5 mass of ff~ per and ~e ax~s 35 of the ~heat:h 16, thi6 beil~g olle encoder unit will provide velocity and aoceleration data to be used in determi~ kinetic ~o~ arising ~n the diF~r mov~.

10 of ffle pinio~ that ~ c~ retracts the diE~per arm 25 relative to ~e saddle 26. P~ ~his ir~put ~e p~oces~r s~an ~culate the distance be~ t:he centr~ of mass of ~e dipper and ~hs axi6 27 of the piv~t ~cticn between ~e ~e 26 a~ t~he bocm 15.

15 ar~ the di~er arm drive the proc~sor ha~ co-ordina~es of ~he centre of mass of the di~r in ~ of ~e tWD fix~ po~*s on ths boam 15~
~ri~ the co-ordinates OI t~he cer~tre of maæs of ~ dipper in re~ect of ~hs fixed points an ~ bo~ it can be det~
20 mat~ratically ~3 s~ain ~at the wei~ht o~ ~ diFlper and its C7~v~y ~ the ~'crain in a ~elected part o~ t~ ~?~rt s~tu~ and 1~he di~o~itic2n of ff~ ~tre of mass o~ ~ diE~r the wei~ht o~ th~ dipper and its corste3~ can be calculated. 1~ su~ a 25 calculati~n a~t will hav~ to 1~ tak~ of ~ r ~ain irx~ucing Accordi~ly, ~y sultably pr~:a~nl~ ~ p~r a~
providing signale ~creto r~rdin~ e positicn o~ t~e ~, and ~e - 30 ~e weight o~ ~e diE~er plus con~ if a~y., It will ba a~eciàted d~V31~t o~ ~e parti~ar math~;atic ~o~la and a E~n based the:l:e~ iB Wit~ll ~ skill of ~l~lt a~ille~8.
In a ~ load~r of ~ c~ ic~ ~ ln Figl~re 1 i~
has been faJnd that a de~irable loca~ian of ~train gauge~; is o~ e vertical n~ of t~ ba~c stay 19. IhQ ~ in tha ba~k stay is of a les~ a~plex natur~ ~ ~ in mar~ ~ areas of the ~ lC~3, ..~ , . ~ . . ,~, .

~Z9~ 7 ar~ has a relati~rely c~enie~t relations~ip to ~e wei~h~ o:e ths di~æ and its contents.
Figure 2 of the drawin~ shaws one ~cti~al a~rar~nt of ~he vari~us e~od~ and processors to perform ~e pres~rt iTIvention, 5 as applied to the di~ ype shovel loader des~ibed wit~ erence to Figure 1.

previc~usly referrad to are r~ s~ted at 81, 82 and 83, and ea~h pr~vide se~ially i~formati~n to ~e secondary pro~essor 85 ~ich 10 pn~par~ th~ encoder information for processing ~y ~e ma~ pmcessor 95. Other basic: informaticn rqardiDg the ~ing c~diticQl of the load~ is pxavided fralQ the sha~el c~trol 86 via ~s interfac~ unit 87 an~ the car~ er 88 to th~ main pr~cessor 95. lhis ~ basic informatioal relate~ to ~e1~her ~e ~hovel is tha c~ra~ candition, 15 ~ t~ hovel is p~ 1~ c~:a~, ~r is ~n a m~ibile state, m~ing be~we~ working site etc. I~is in~ormati~ iE~ rel~var~t and ~efore ~e ~r shauld ~e a weight calculaticn.
5~a strain gauge uni~ 91 ar~ 92 are ma~ of the two .20 u~ me~ers fo~ ~e ~ stay 19 in Figur~ 1 and pro~e a signal prcportional to t~e ~train in saiLd bacllc stay. Ih:Ls ~ignal i also passed ~ ~e ~ 88 to ~ main pro~sor 95.
I~B main proae~sor is ~ogr2~ as pre~ia~ly discua~cd to calculatçl fr~ th0 i~t8 ~ weight of ~.bu~t and conte~
25 each positian and, 10ad d~ln~ti~n, and to pruvide an avl3rage weight ~ resultar~t wei~ht o~ mat~rial delivered each cycle a~
calculated ~y: ~ main procQssor 95 i~ passed to ~he so1id ~;ta~

30 a radic) 1ir~c tranc:l~ ccimna~ o~ a r~te base c~ tr~s~er i~o~ti~ fn~m the se~ary p~sor ~y to ~ base via t~Ds radio ~m 98 and radio unit 99.
me opcrator ~isplay 96 is suita~1y 10cated ror ~e ~wel cgp~ator, and via ~a grap~ic prooesso~ 94 ~eceive~
35 regulæly updated ~nfor~ ion r~ding ~ weight o~ material delivered ea~h ~yclQ of ~e ~ and ~he total weight deliYered ~o each tn~c.
Sui~able = clal1y availabla pm~Gors fo3: USQ its ;~ .
., .

8~

abave des~ibad arrang~nerrt are:
~ain Processor - M~torola MC68000 Sec~ary ~rocessor - ~!lbtorola ~C6802 GraE~hic Pr~cessor - M~torola MC6802 Re~erring naw to ~he s~lified logic diagr~ of Figure 3 and 4 the basic decision and cpera~ions o~ ~e p~sor will be des~ibed.
qhis ~ o~ decisions and cperatio~s is per~ormed as folla~s at a set time inte~al ~e ~e shovel is ~n c~peraticn.
1. data gather~d fr~n ~e vari~us er~coders and t~he st:rain gau~
2. calculat0 ths kin~natic b~havia~ OI ~he di~per arm from ~e encod~ infon~ati~;

3. calculate t~ per load fr~ e informati ~or ~e particular kin~c b~ihaviaur of t~he diE~per;
15 4. d0tencine if ~ di~per door i~ ~pen.
a. If t:~e d~or iB ~, i~ic:ating that the di~per is ~n ~it a~ d~ping a load, ffbe calculated ~LiE~#r loa~ is stored ~or s~ibs~erlt averaging.
b. If ~he di~eer do~r ~ clo6ed t~ di~per may be in o~e of ff~
1. "diggirlg" mat~rial to fill the diE~.
. ~ 2. "swinging", ~at is in translt, bet~ ~e d~pper lo~ ar~l diFper ~ing positic~ns.
3. "waiting" in a ~ositlcn to ~qp into ~ tru~c, th~

dlEper is as pnvlca~ly di~ and ther~ proceed in acsordar~a ~rith tbat d~termin4ti~n.
l~a de~i~icns an~ ~ticru of ffis ~ follaw~3d in t o Figure 4 ~ the t~7res headin~ 'lDigg:Lr~'~, "$wir~ir~" a~d : : "Wa:itin~".
Digging.
1. determina ~e sta~ of tlle di~per at ~ t~ of ffle pr~vious ~1~
~: a. if ~e di~ 7as also digg~ in ~e ~reviau~3 ~cle di~per loa~ calculatian i~ n~t m~ui~ed to be storad, . ~ord~gly the store~l avera~e di~ load will b~

, lZ~819~7 "diggir~

na~ average~ ffie di}~per load calcula~ion; s~ored durin~
~rn ~wir~ of ~ di~per to d~termine ~e average diE~r weight. ~e processor will have s~ore~ fflerein ffle avera~ ~ull di~er wei~jht a~ det~ ~uring ~he pr~dir~ ~ n~t of th~ diE~per fr~ ~e digging to t~he d~ing po~itio~, and naw calcula~ weight o~

ma~erial is 'crdtted to a ~asy ~r ar~ stored for si~:~t ret~i0val su~ aE~ ~y trar~issic~ k~ radio to a rc~to ~ge or~ ~ p~sing facilit:y.
et~ned ~dl ~t is also t~itt~ to visua~ display fo~ sh~vel a~ator ~/l~g. ~ftcr stor3d~ av~age di~er we~ to zero and ths ~ pr~wiouR ~ta~ D~y s~t to "digging".

Dete~ino` tho ~ -d tha dipper at t:hs ti~e of t~ p~via~
cycle.

a ~c .Is h~e that ~Q ~ireatian o~ ~Q same and iî 80 ~va dipp~r load. is calcula~ed an~l stor3d, and ths curr~t avo~ diE~pQr load for ~at partia~lar sw~ ig cal~ated ~c~r ~ ~gplay. ~i~ s~ is re~d in d~e~ o~ s~ng: as: pr~vi~usly: di~sed. 1~

~: depart~ an~ a ~:rth~ tn~k i~ to mava i~to po~itian. 'Iha ', ' ' .
"

1~ 7 proces~,or i~ thus a~vised a c~ ge og truc~k is in prog~e~s processor ar~l stored.
Waiting.

so ~at: the c~t calculated di~per load is stored and t~ previa~s state set at waiting. Ih~ c~ycïe r~peats ~til a char~e of 6tate i8 signal~d.

state at the en~l of a swing in one dire~i~, wi~h t~e di~per load~d, and leaves ~e waiking state a~ t~he ~t of a ~ in ~e c~site ~ic~. While in ~e waitir~g state ~e di~ doc)r will be aperated to ~pen ~ ~it ~e load in t~he ~k. Ihus the cparator 15 initiated ~peni~ of the dipper door is used to signal to the pmcessor a ~ e in directi~ o~ swi~. Similæly ffle closing oi~ tha di~per door occurs at ~e endl o~ ~e r~rn swing of the dipper ~ e digging position ar~ so alorsg indicat~ ~he ~ ne~ct ~hange of direction of swing of ffle dip~.
Re~er~ce ha~ p~via~3ly been ma~ to ~tical co7~pled to ff~s electric mator~ transmi~i~s whi~h driva the win~

~e positi~ a~ ~ ment o~ ~ re~ti~e ~=~ts. ~code~ ~or ~s purpos~ nay b~ of ar~ ~n fflnn havir~ ~s r~ired capaoity 25 an~ accurac~y. C~na c~ngparatively ~i~ple ~ut e~ective form of en~o~
i~ ~ diagx~na~lcally in Figu~ 5.
qha er~ ca~risin~ put sba~t 102, ~d in 103 and lM, ar~ carryirs3 ~e first coded di~;c 105 and pini~
106. q~a end ~ 107 of t~ ~aft 102 ~3 in use ~pl~
30 to th~ ~itor or tran~issicn d~ivir~ ~he =~neot, ~e posit~c~ o~
pinicdl 106 drives ~he g 108 m~ an the lay shaft - 109, ~nted ffie gear 110. ~a ~ 109 ~s su~o~ted in bearing~ 111 at aach er~ he ~ 109 and geæ~ 108 and 110 35 rota~ in ~iær~ ar 110 dri~es gear 112, m~nt~ on ~iha~ 113 :
., 1~4~'7 The two gears trains 106 - 108 and 110 - 112 pravide a daible reduction in ~;peed be~ ~e ~irst and secon~l coded discs 105 an~

114 will a~vance one cod~ in~erval for eac:h reYolution of the first 5 coded di~c 105. Ihe ~ reduction betweerl the ~irst coded disc and ~he me~er drivir~f it is selected, having r~gard to ~e relative coded disc 114 is re~ired to effect no m~re than ane aa~lete r~volution for the full e~;t of mov~ment of ~he monitor~xl ~onent.
10Ea~h ooded disc 105, 114 is provid~d with arl cptical oode pat~n a~d its peri~ area, of a~y suital31e form, su~ as t~he 'Grey Pa~tern' . A li~t salrce an~ re~eiver ~its 120 a~xl 121 ar~
pravided for ~ ~iv~ 105t 114 to ge~atQ wit~
perimetal pa~n a digltal 8~ irxlicative of ~he rota~io~al 15 positio~ of each disc. It will ba al~preciat~d that ~he signa:L fram ~e firsi disc 105 divides eac~h ~ o~ o~ disc 114 }:y the of intervals ~ the first disc. Acoordir~ly, the a~pu:t frc~n the two discs provide an ac~rate tra~king of t~e position of the c~nent bein~ monitored.
20~ itic~n, the signal frcm the firsk coded disc can be process~d to provid~ velocity and aoceleration da~a in r~ of ~he m~itored ~
It will i~ ~d~l that th~3 ~th~matical ~onrula upon ~idh t~e p~ of th~ processors is based ~rill bo deper~ent on a 25 r~r OI fact~ ir~ 'chs gen~al ge~ of ~ ~ihovel loa~
5t~ ~o~tin~ the h~t, the partia~lar lo~ation o~ ~e ~n gauge~ or t:he liX~ cn ~ ~tmc~, arxl the fixed poi~ts selected on .

30 w~ wn in ~ æt and ~r those ~killed in the arc.

Claims

Claims:

1. A method of measuring the quantity of material delivered per cycle by a shovel loader having a bucket to hold the material to be delivered, the bucket being movable between a loaded and unloading positions, said bucket being supported from a structure during movement between said positions, said method comprising determining the position of the bucket in respect to a selected location on said structure in the form of a processable position signal at one or more intervals during said movement, determining the load at a selected location within said structure where the load is related to the mass of the bucket and bucket contents in the form of a processable load signal at said interval or intervals, and processing said position and load signals to determine the mass of the bucket and bucket contents at said interval or intervals.

2. A method as claimed in claim 1 wherein said position determination and said load determination are made at a plurality of intervals during said movement of the bucket between the loaded and unloading positions, processing the position and load signals for each interval determination, and averaging the determined mass of the bucket and bucket contents for the plurality of determination made during said movement.

3. A method as claimed in claim 1 wherein first position determinations and first load determinations are made as the bucket moves from the loaded to the unloading positions, and second position determinations and second load determinations are made as the bucket returns from the unloading position toward the loaded position, processing said position and load signals from said first position and load determinations to determine the mass of the bucket and bucket contents when the bucket is loaded, processing said position and load signals from said second position and load determinations to determine the mass of the bucket and bucket contents after the bucket has been unloaded, and processing the determined mass of the loaded and unloaded bucket to determine the mass of material delivered from the bucket.

4. A method as claimed in any one of claims 1 to 3, wherein the position of the bucket is determined by determining the distance from a selected point in the bucket to two spaced fixed points of the structure, said two spaced points having a fixed relation to the location at which the load in the structure is determined.

5. A method as claimed in any one of claims 1 to 3, wherein the structure is mounted for movement about a vertical axis to effect movement of the bucket between said loaded and unloading positions.

6. A method as claimed in any one of claims 1 to 3, wherein the structure is mounted for movement about a vertical axis to effect movement of the bucket between said loaded and unloading positions and said position determinations and said load determinations are made at fixed time intervals during at least part of the movement of the structure about said vertical axis to and from the bucket unloading position.

7. A method as claimed in any one of claims 1 to 3, wherein position and load determinations are processed to provide mass determinations only when the bucket is at or above a predetermined height with respect to the structure.

8. A method as claimed in any one of claims 1 to 3, wherein the velocity and acceleration of the structure and the bucket are determined during the movement of the bucket between said loaded and unloading positions in the form of processable kinetic signals, and said kinetic signals are processed to determine that portion of the load at said selected location resulting from said velocity and acceleration and effecting correction to load determination accordingly.

9. A method as claimed in any one of claims 1 to 3, wherein the load at said selected location in the structure is determined by a load cell means that produces an electrical signal proportional to the strain in the structure at said location.

10. A method of measuring the quantity of material delivered per cycle by a shovel loader comprising a base, a platform supported on the base for rotation relative thereto about a vertical axis, a boom connected to the platform at the lower end and an upper portion to a stay structure mounted on the platform so the boom extends upwardly and outwardly from the platform, and a bucket supported suspended from the boom and displacable therefrom in a vertical and horizontal direction, said method comprising determining in the form of electrical signals the position of the bucket with respect to a selected location in the boom or stay structure at one or a number of intervals in the movement of the boom from a bucket loading to a bucket unloading position, providing inputs, generated by said signals to an electronic processor programmed to calculate therefrom the total mass of the bucket and contents at each interval, making further such determinations and inputs to the processor at one or a number of intervals in the movement of the bucket in the reverse direction between said positions, and processing said inputs in the processor to provide a difference between the mass of the bucket during the two movements.

11. In a shovel loader having a bucket supported from a structure, the structure being movable to locate the bucket in respective loaded and unloading positions, and apparatus for measuring the quantity of material delivered by the bucket per shovel cycle, said apparatus comprising means to determine the position of the bucket with respect to a selected location in the structure at one or more intervals during said movement of the bucket, means to determine the load at a selected location within the structure where the load is related to the mass of the bucket and bucket contents at said one or more intervals during said movement of the bucket, means to produce a processable load signal indicative of the determined load at said location, and processor means to receive said position and load signals and determine therefrom the mass of the bucket and bucket contents.

12. In the combination claimed in claim 11 wherein the means to determine the shovel position is adapted to determine the distance of a fixed point on the bucket from each of two spaced fixed points on the structure, and the position signal means produces respective signals indicative of each of said distances for supply to the processor means.

13. In the combination claimed in claim 11 wherein the structure is pivotally about a vertical axis to move the bucket between said loaded and unloading position, and said position and load determining means are operable at preselected intervals during said pivotal movement between said positions in either direction.

14. In the combination claimed in claim 11 wherein the means to determine the shovel position is adapted to determine the distance of a fixed point on the bucket from each of two spaced fixed points on the structure, and the position signal means produces respective signals indicative of each of said distances for supply to the processor means and wherein the structure is pivotally about a vertical axis to move the bucket between said loaded and unloading position, and said position and load determining means are operable at preselected intervals during said pivotal movement between said positions in either direction.

15. The combination as claimed in claim 11 wherein the position determining means and the load determining means are adapted to respectively make bucket position and load first determinations as the bucket moves from the loaded to the unloading position, and second determinations as the bucket moves from the unloading to the loaded position, and said processor means determines the average mass of the loaded bucket and contents from said first determinations, the average mass of the unloaded bucket and contents from said second determinations, and the differences between said average masses.

16. The combination as claimed in any one of claims 11 to 13 wherein there is provided means to provide a processable signal indicative of the velocity and acceleration of the bucket and the structure when the bucket is moving between the loaded and unloading positions, said processor being programmed to determine from said signal the kinetic load existing at said location in the structure from the velocity and acceleration of the bucket and structure.

17. The combination as claimed in claim 14 or 15 wherein there is provided means to provide a processable signal indicative of the velocity and acceleration of the bucket and the structure when the bucket is moving between the loaded and unloading positions, said processor being programmed to determine from said signal the kinetic load existing at said location in the structure from the velocity and acceleration of the bucket and structure.

18. The combination as claimed in any one of claims 11 to 13 wherein the structure includes a platform, an upwardly extending boom connected at the lower end to the platform, a stay rigidly connected to the platform, and a brace connecting the upper end of the boom to said stay, said bucket being suspended from said boom, and said selected location in the structure being in said stay.

19. The combination as claimed in claim 14, 15 or 17.
wherein the structure includes a platform, an upwardly extending boom connected at the lower end to the platform, a stay rigidly connected to the platform, and a brace connecting the upper end of the boom to said stay, said bucket being suspended from said boom, and said selected location in the structure being in said stay.

20. A method as claimed in claim 1 wherein said position determination and said load determination are made at a plurality of intervals during said movement of the bucket between the loaded and unloading positions, processing the position and load signals for each interval determination, and averaging the determined mass of the bucket and bucket contents for the plurality of determination made during said movement and wherein said first position determinations and first load determinations are made as the bucket moves from the loaded to the unloading positions, and second position determinations and second load determinations are made as the bucket returns from the unloading position toward the loaded position, processing said position and load signals from said first position and load determinations to determine the mass of the bucket and bucket contents when the bucket is loaded, processing said position and load signals from said second position and load determinations to determine the mass of the bucket and bucket contents after the bucket has been unloaded, and processing the determined mass of the loaded and unloaded bucket to determine the mass of material delivered from the bucket.

21. A method as claimed in claim 20 wherein the structure is mounted for movement about a vertical axis to effect movement of the bucket between said loaded and unloading positions.

22. A method as claimed in claim 20 or 21, wherein the structure is mounted for movement about a vertical axis to effect movement of the bucket between said loaded and unloading positions and said position determinations and said load determinations are made a fixed time intervals during at least part of the movement of the structure about said vertical axis to and from the bucket unloading position.

23. A method as claimed in any one of claims 20 or 21, wherein the velocity and acceleration of the structure and the bucket are determined during the movement of the bucket between said loaded and unloading positions in the form of processable kinetic signals, and said kinetic signals are processed to determine that portion of the load at said selected location resulting from said velocity and acceleration and effecting correction to load determination accordingly.